Probe head for dnp-nmr spectrometer with integrated mirror in the temperature control gas line for sample illumination

An NMR probe head, configured for use in dynamic nuclear polarization, comprising:

• a sample holder for receiving an elongated sample vessel with a sample substance in a sample volume surrounded by an RF coil during NMR measuring mode,
• a temperature control device for temperature control of the sample substance in the sample vessel during the NMR measuring mode, wherein the temperature control device of the NMR probe head comprises a VT channel through which, in NMR measuring mode, temperature control fluid can be supplied to the sample vessel for temperature control of the sample substance,
• a microwave guide for supplying microwave radiation into the sample volume,
• an illumination apparatus having a light guide for photoinduced electron excitation of sample substance in the sample volume, wherein a sample-side end of the light guide is arranged in the VT channel, and
• a deflecting mirror arranged in the VT channel between the sample-side end of the light guide and the sample vessel, the deflecting mirror directing light exiting the light guide onto the sample substance in the sample volume of the sample vessel during NMR measuring mode.